Exception throwed when refreshing token

[LuigiVessella]

I'm working on my web app and I'm using this plugin to implement oauth2 login.
Login and logout are working fine but when i call my refresh() function:
`Future<AuthorizationResponse?> refresh() async {
if (discoveryDocument == null) {
await _fetchConfiguration(); // Recupera la configurazione se necessario
}

RefreshRequest request = RefreshRequest(
  
    clientId: clientId,
    scopes: ["openid", "profile", "email"],
    refreshToken: identity!.refreshToken!,
    configuration: discoveryDocument!,
    autoRefresh: true);

try {
  final response = await OpenIdConnect.refreshToken(request: request);

  identity = response;

  _isLogged = true;
  return response;
} on Exception catch (e) {
  throw Exception('Error during refresh OpenID Connect: $e');
}

}i got this error:Error: Exception: Error during refresh OpenID Connect: Request Failed: [error: request_failed, description: invalid_client: Invalid client or Invalid
client credentials]
dart-sdk/lib/internal/js_dev_runtime/private/ddc_runtime/errors.dart 297:3 throw
packages/greenway/services/network/logger_web.dart 85:7 refresh
dart-sdk/lib/_internal/js_dev_runtime/patch/async_patch.dart 60:31 `